Tiny untethered robot-insects take flight
UWashington engineers designed RoboFly to take flight by using a narrow invisible laser beam to allow for its wings to flutter.
Buzz! Buzz! It could be a bug or butterfly. Or it could be an insect-sized flying robot.
Engineers at the University of Washington have found a way to make tiny robotic insects a reality. Unlike traditional drones that use propellers, these mini robots are able to soar through the air by fluttering tiny wings. For the most part, current flying robo-insects still need to be tethered to the ground and power/control electronics are too heavy for these miniature robots to carry.
The team is found a way to cut the cord and add a brain, enabling their RoboFly to take its first independent flaps. Slightly heavier than a toothpick, the team’s RoboFly is powered by a laser beam and uses a mini onboard circuit that converts the laser energy into enough electricity to operate the wings.
One of the biggest challenge for the team was getting the robot’s wings to flap, which requires significant power consumption.
UWashington engineer’s previously dealt with this issue by including a leash on its robo-insect, RoboBee. Co-author Sawyer Fuller, an assistant professor in the UW Department of Mechanical Engineering, explains that RoboBee was able to receive power and control through wires from the ground without the bulky power source and controllers needing to be affixed to the bot.
Fuller and team decided to take this robo-insect one step further, by using a narrow invisible laser beam to power the robot. They pointed the laser beam at a photovoltaic cell, which is attached above RoboFly and converts the laser light into electricity. However, the laser along does not provide enough voltage to power the wings.
To deal with this issue, the team designed a circuit that boosted the seven volts coming out of the photovoltaic cell up to the 240 volts needed for flight.
But what is a flying robo-insect without a brain? The engineers were able to give RoboFly control over its own wings by adding a microcontroller to the same circuit.
“The microcontroller acts like a real fly’s brain telling wing muscles when to fire,” said co-author Vikram Iyer, a doctoral student in the UW Department of Electrical Engineering. “On RoboFly, it tells the wings things like ‘flap hard now’ or ‘don’t flap.'”
Specifically, the controller sends voltage in waves to mimic the fluttering of a real insect’s wings.
RoboFly has mastered take off and landing. Once its photovoltaic cell is out of the direct line of sight of the laser, the robot runs out of power and lands. However, the team is working towards steering the laser to enable RoboFly to hover and fly around.
Future RoboFlies can also look forward to more advanced brains and sensor systems that help the robots navigate and complete tasks on their own, Fuller said.